1. Field of the Invention
The invention is directed to a stator for an electric machine having an annular stator yoke at which a plurality of radially projecting stator teeth is arranged in circumferential direction, coils with coil terminals being arranged at these stator teeth. Annular connection conductors are provided at the stator for connecting to the coil terminals. These annular connection conductors are arranged so as to be concentric to one another and electrically insulated relative to one another in a connection area of a carrier member, this connection area being located next to the coils, and are connected therein to the coil terminals in a predetermined manner.
2. Description of the Related Art
A stator of the type mentioned above is described in US2007/0262664. The coils are made from a wire wound around two insulating bodies arranged at the front of the stator. The ends of the coils are bent out of the winding plane in radial direction and are inserted into wire guide portions at an insulating body which penetrate into the receiving space of a supporting structure accommodating the connection conductors. The ends of the coils are bent once again in this receiving space, specifically in circumferential direction of the stator, for connecting to the connection conductors. When mounting the stator of the electric machine, which is constructed in this case as an external rotor, the stator coils are initially fitted to the stator teeth radially from the outer side and, in another step, the supporting structure with the connection conductors is pushed on from the front side of the stator facing the connection side until coming into contact with the wire guide portions. The ends of the coils can then be connected to the connection conductors by means of separate terminal elements.
The connection arrangement mentioned above is advantageous in an external rotor motor, but can only be used conditionally with an internal rotor. Irrespective of the wiring variants, the handling of the ends of the coils and particularly the bending points is critical because the sensitive lacquer coating at the latter can tear and be penetrated by moisture which can subsequently lead to corrosion and to the failure of winding components.